Footage and photos of the alleged chemical attack in Syria, which the US cites as the reason for a planned military intervention, had been fabricated in advance, speakers told a UN human rights conference in Geneva.

Members of the conference were presented accounts of international experts, Syrian public figures and Russian news reporters covering the Syrian conflict, which back Russia’s opposition to the US plans, the Russian Foreign Ministry said in a statement.

The speakers argued that the suspected sarin gas attack near Damascus on August 21 was likely a provocation of the rebel opposition forces and that a military action against Syrian government will likely result in civilian casualties and a humanitarian catastrophe affecting the entire region.

The possible attack by US military without a UN Security Council mandate would violate international law and should be prevented by the United Nations, some of the speakers said.

Evidence for the Russian case, including numerous eyewitness reports and results of investigations of the chemical weapon incident by activists, was handed over to a UN commission of experts probing the Syrian crisis, the ministry said.

The Obama administration voiced an intention to use military force in Syria after reports of mass deaths in Eastern Houla, a neighborhood of Damascus, which killed more than 1,400 people according to US estimates. Washington says the deaths was due to a chemical weapons attack of the Syrian army on rebel forces and says it plans to use force to prevent such incidents in the future.

Russia is convinced that the chemical incident was a provocation by rebel forces, which staged a false flag attack to drag the US into the conflict and capitalize on the damage that the Syrian army is likely to sustain in the American intervention.

An increasing number of reports is backing Russia’s position, with local witnesses, US and British former intelligence professionals and Europeans recently released from rebel captivity all speaking for a provocation scenario.

In the latest development this week a possible way to de-escalate the tension was voiced, which would involve the Srian government handing over control of his chemical arsenal to the international community. The plan was backed by Russia, China and Syria's main ally Iran, while Syria said it will review it.

Mixed signals over the plan came from the US.

President Obama said such a move from Damascus would make him put the military action plan on pause.

Many sources predict that that opposition rebels might be planning a chemical weapons attack in Israel. The possible attack would be carried out from the territory supposedly controlled by the Syrian government and would trigger another round of escalation, leaving little hope of defusing the tension.